1. Field of the invention
The present invention relates t o a bolt/nut unfastening preventing structure which makes it impossible to turn a fastening nut relative to its corresponding bolt engaged with this nut after completion of their fastening operation, thereby preventing assembled members fastened by these nut and bolt from being disassembled.
2. Description of the Related Art
Recently, some pieces of news reporting seditious events have reached to us that some of bolts fixing an electric power transmission lattice-type tower to its base, and also some bolts fixing a part of the rails of the Japanese railroad "Shinkansen" to its base are illegally unfastened or removed by someone not authorized. The causes of the above events are easiness in unfastening the bolt and the nut each having a conventional fastening structure, in which both a head portion of the bolt and the nut fitted to a shank portion of the bolt are carelessly exposed to the outside, and thereby permitting anyone to unfasten these bolt a nd nut in an easy manner.